	S	M	L	XL
Stack	608mm	617mm	626mm	635mm
Reach	425mm	450mm	475mm	500mm
Stack to Reach Ratio	1.43:1	1.37:1	1.32:1	1.27:1
Seat Tube Length, Unknown	400mm	430mm	460mm	490mm
Top Tube Length, Effective/Horizontal Center	588mm	613mm	638mm	663mm
Top Tube Slope	22.8deg	19.8deg	17deg	14.5deg
Head Tube Angle	66deg	66deg	66deg	66deg
Seat Tube Angle	75deg	75deg	75deg	75deg
Bottom Bracket Drop	65mm	65mm	65mm	65mm
Bottom Bracket Height	309.5mm	309.5mm	309.5mm	309.5mm
Chainstay Length	427mm	427mm	427mm	427mm
Chainstay Length Horizontal	422mm	422mm	422mm	422mm
Front-Center	720.9mm	746.8mm	772.7mm	798.6mm
Front-Center Horizontal	718mm	744mm	770mm	796mm
Wheelbase	1140mm	1166mm	1192mm	1218mm
Fork Offset/Rake	46.8mm	44mm	41.3mm	38.6mm
Trail	115.5mm very high	118.5mm very high	121.5mm very high	124.5mm very high
Mechanical Trail	105.5mm	108.3mm	111mm	113.8mm
Wheel Flop	42.9mm	44mm	45.2mm	46.3mm
Standover Height	728mm	738mm	748mm	758mm
Tire to Pedal Spindle	176.4mm 170 mm cranks	202.3mm 170 mm cranks	228.2mm 170 mm cranks	254.1mm 170 mm cranks
Pedal Spindle to Ground Clearance	139.5mm 170 mm cranks	139.5mm 170 mm cranks	139.5mm 170 mm cranks	139.5mm 170 mm cranks

Very Upright

Somewhat Upright

Average

Somewhat Aggressive

Very Aggressive

The Bike Insights Upright/Aggressive scale is based on analysis of a bike’s proportions relative to similar sized bikes in the same category.

Category Trend

2026 Pipedream Cycles Sirius S6 CrMo

Geometry